A. From the picture, the vertex is at (-2, 6)
B. From the picture, the vertex is a maximum. The maximum is 6
C. The domain is the set of all possible values of the x-variable. For any parabola, the domain is (-∞, ∞)
The range is the set of all possible values of the y-variable. From its maximum, the range of the parabola is (-∞, 6]